agora inbox for [email protected]  

help / color / mirror / Atom feed

[PATCH v1 1/4] autovac: save all relopts instead of just avopts
340+ messages / 2 participants
[nested] [flat]

* [PATCH v1 1/4] autovac: save all relopts instead of just avopts
@ 2025-06-23 19:07  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Nathan Bossart @ 2025-06-23 19:07 UTC (permalink / raw)

---
 src/backend/postmaster/autovacuum.c | 119 ++++++++++------------------
 1 file changed, 43 insertions(+), 76 deletions(-)

diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 451fb90a610..f86c9fed853 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -192,8 +192,8 @@ typedef struct av_relation
 	Oid			ar_toastrelid;	/* hash key - must be first */
 	Oid			ar_relid;
 	bool		ar_hasrelopts;
-	AutoVacOpts ar_reloptions;	/* copy of AutoVacOpts from the main table's
-								 * reloptions, or NULL if none */
+	StdRdOptions ar_reloptions; /* copy of main table's reloptions, or NULL if
+								 * none */
 } av_relation;
 
 /* struct to keep track of tables to vacuum and/or analyze, after rechecking */
@@ -333,11 +333,11 @@ static void FreeWorkerInfo(int code, Datum arg);
 static autovac_table *table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 											TupleDesc pg_class_desc,
 											int effective_multixact_freeze_max_age);
-static void recheck_relation_needs_vacanalyze(Oid relid, AutoVacOpts *avopts,
+static void recheck_relation_needs_vacanalyze(Oid relid, StdRdOptions *relopts,
 											  Form_pg_class classForm,
 											  int effective_multixact_freeze_max_age,
 											  bool *dovacuum, bool *doanalyze, bool *wraparound);
-static void relation_needs_vacanalyze(Oid relid, AutoVacOpts *relopts,
+static void relation_needs_vacanalyze(Oid relid, StdRdOptions *relopts,
 									  Form_pg_class classForm,
 									  PgStat_StatTabEntry *tabentry,
 									  int effective_multixact_freeze_max_age,
@@ -345,8 +345,6 @@ static void relation_needs_vacanalyze(Oid relid, AutoVacOpts *relopts,
 
 static void autovacuum_do_vac_analyze(autovac_table *tab,
 									  BufferAccessStrategy bstrategy);
-static AutoVacOpts *extract_autovac_opts(HeapTuple tup,
-										 TupleDesc pg_class_desc);
 static void perform_work_item(AutoVacuumWorkItem *workitem);
 static void autovac_report_activity(autovac_table *tab);
 static void autovac_report_workitem(AutoVacuumWorkItem *workitem,
@@ -1995,7 +1993,7 @@ do_autovacuum(void)
 	{
 		Form_pg_class classForm = (Form_pg_class) GETSTRUCT(tuple);
 		PgStat_StatTabEntry *tabentry;
-		AutoVacOpts *relopts;
+		StdRdOptions *relopts;
 		Oid			relid;
 		bool		dovacuum;
 		bool		doanalyze;
@@ -2033,7 +2031,7 @@ do_autovacuum(void)
 		}
 
 		/* Fetch reloptions and the pgstat entry for this table */
-		relopts = extract_autovac_opts(tuple, pg_class_desc);
+		relopts = (StdRdOptions *) extractRelOptions(tuple, pg_class_desc, NULL);
 		tabentry = pgstat_fetch_stat_tabentry_ext(classForm->relisshared,
 												  relid);
 
@@ -2069,7 +2067,7 @@ do_autovacuum(void)
 				{
 					hentry->ar_hasrelopts = true;
 					memcpy(&hentry->ar_reloptions, relopts,
-						   sizeof(AutoVacOpts));
+						   sizeof(StdRdOptions));
 				}
 			}
 		}
@@ -2095,7 +2093,7 @@ do_autovacuum(void)
 		Form_pg_class classForm = (Form_pg_class) GETSTRUCT(tuple);
 		PgStat_StatTabEntry *tabentry;
 		Oid			relid;
-		AutoVacOpts *relopts;
+		StdRdOptions *relopts;
 		bool		free_relopts = false;
 		bool		dovacuum;
 		bool		doanalyze;
@@ -2113,7 +2111,7 @@ do_autovacuum(void)
 		 * fetch reloptions -- if this toast table does not have them, try the
 		 * main rel
 		 */
-		relopts = extract_autovac_opts(tuple, pg_class_desc);
+		relopts = (StdRdOptions *) extractRelOptions(tuple, pg_class_desc, NULL);
 		if (relopts)
 			free_relopts = true;
 		else
@@ -2701,39 +2699,6 @@ deleted2:
 		pfree(cur_relname);
 }
 
-/*
- * extract_autovac_opts
- *
- * Given a relation's pg_class tuple, return a palloc'd copy of the
- * AutoVacOpts portion of reloptions, if set; otherwise, return NULL.
- *
- * Note: callers do not have a relation lock on the table at this point,
- * so the table could have been dropped, and its catalog rows gone, after
- * we acquired the pg_class row.  If pg_class had a TOAST table, this would
- * be a risk; fortunately, it doesn't.
- */
-static AutoVacOpts *
-extract_autovac_opts(HeapTuple tup, TupleDesc pg_class_desc)
-{
-	bytea	   *relopts;
-	AutoVacOpts *av;
-
-	Assert(((Form_pg_class) GETSTRUCT(tup))->relkind == RELKIND_RELATION ||
-		   ((Form_pg_class) GETSTRUCT(tup))->relkind == RELKIND_MATVIEW ||
-		   ((Form_pg_class) GETSTRUCT(tup))->relkind == RELKIND_TOASTVALUE);
-
-	relopts = extractRelOptions(tup, pg_class_desc, NULL);
-	if (relopts == NULL)
-		return NULL;
-
-	av = palloc(sizeof(AutoVacOpts));
-	memcpy(av, &(((StdRdOptions *) relopts)->autovacuum), sizeof(AutoVacOpts));
-	pfree(relopts);
-
-	return av;
-}
-
-
 /*
  * table_recheck_autovac
  *
@@ -2753,8 +2718,8 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 	bool		doanalyze;
 	autovac_table *tab = NULL;
 	bool		wraparound;
-	AutoVacOpts *avopts;
-	bool		free_avopts = false;
+	StdRdOptions *relopts;
+	bool		free_relopts = false;
 
 	/* fetch the relation's relcache entry */
 	classTup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
@@ -2766,9 +2731,9 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 	 * Get the applicable reloptions.  If it is a TOAST table, try to get the
 	 * main table reloptions if the toast table itself doesn't have.
 	 */
-	avopts = extract_autovac_opts(classTup, pg_class_desc);
-	if (avopts)
-		free_avopts = true;
+	relopts = (StdRdOptions *) extractRelOptions(classTup, pg_class_desc, NULL);
+	if (relopts)
+		free_relopts = true;
 	else if (classForm->relkind == RELKIND_TOASTVALUE &&
 			 table_toast_map != NULL)
 	{
@@ -2777,10 +2742,10 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 
 		hentry = hash_search(table_toast_map, &relid, HASH_FIND, &found);
 		if (found && hentry->ar_hasrelopts)
-			avopts = &hentry->ar_reloptions;
+			relopts = &hentry->ar_reloptions;
 	}
 
-	recheck_relation_needs_vacanalyze(relid, avopts, classForm,
+	recheck_relation_needs_vacanalyze(relid, relopts, classForm,
 									  effective_multixact_freeze_max_age,
 									  &dovacuum, &doanalyze, &wraparound);
 
@@ -2792,6 +2757,7 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 		int			multixact_freeze_min_age;
 		int			multixact_freeze_table_age;
 		int			log_min_duration;
+		AutoVacOpts *avopts = (relopts ? &relopts->autovacuum : NULL);
 
 		/*
 		 * Calculate the vacuum cost parameters and the freeze ages.  If there
@@ -2879,8 +2845,8 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 						 avopts->vacuum_cost_delay >= 0));
 	}
 
-	if (free_avopts)
-		pfree(avopts);
+	if (free_relopts)
+		pfree(relopts);
 	heap_freetuple(classTup);
 	return tab;
 }
@@ -2895,7 +2861,7 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
  */
 static void
 recheck_relation_needs_vacanalyze(Oid relid,
-								  AutoVacOpts *avopts,
+								  StdRdOptions *relopts,
 								  Form_pg_class classForm,
 								  int effective_multixact_freeze_max_age,
 								  bool *dovacuum,
@@ -2908,7 +2874,7 @@ recheck_relation_needs_vacanalyze(Oid relid,
 	tabentry = pgstat_fetch_stat_tabentry_ext(classForm->relisshared,
 											  relid);
 
-	relation_needs_vacanalyze(relid, avopts, classForm, tabentry,
+	relation_needs_vacanalyze(relid, relopts, classForm, tabentry,
 							  effective_multixact_freeze_max_age,
 							  dovacuum, doanalyze, wraparound);
 
@@ -2928,7 +2894,7 @@ recheck_relation_needs_vacanalyze(Oid relid,
  * "dovacuum" and "doanalyze", respectively.  Also return whether the vacuum is
  * being forced because of Xid or multixact wraparound.
  *
- * relopts is a pointer to the AutoVacOpts options (either for itself in the
+ * relopts is a pointer to the StdRdOptions options (either for itself in the
  * case of a plain table, or for either itself or its parent table in the case
  * of a TOAST table), NULL if none; tabentry is the pgstats entry, which can be
  * NULL.
@@ -2962,7 +2928,7 @@ recheck_relation_needs_vacanalyze(Oid relid,
  */
 static void
 relation_needs_vacanalyze(Oid relid,
-						  AutoVacOpts *relopts,
+						  StdRdOptions *relopts,
 						  Form_pg_class classForm,
 						  PgStat_StatTabEntry *tabentry,
 						  int effective_multixact_freeze_max_age,
@@ -2973,6 +2939,7 @@ relation_needs_vacanalyze(Oid relid,
 {
 	bool		force_vacuum;
 	bool		av_enabled;
+	AutoVacOpts *avopts = (relopts ? &relopts->autovacuum : NULL);
 
 	/* constants from reloptions or GUC variables */
 	int			vac_base_thresh,
@@ -3010,45 +2977,45 @@ relation_needs_vacanalyze(Oid relid,
 	 */
 
 	/* -1 in autovac setting means use plain vacuum_scale_factor */
-	vac_scale_factor = (relopts && relopts->vacuum_scale_factor >= 0)
-		? relopts->vacuum_scale_factor
+	vac_scale_factor = (avopts && avopts->vacuum_scale_factor >= 0)
+		? avopts->vacuum_scale_factor
 		: autovacuum_vac_scale;
 
-	vac_base_thresh = (relopts && relopts->vacuum_threshold >= 0)
-		? relopts->vacuum_threshold
+	vac_base_thresh = (avopts && avopts->vacuum_threshold >= 0)
+		? avopts->vacuum_threshold
 		: autovacuum_vac_thresh;
 
 	/* -1 is used to disable max threshold */
-	vac_max_thresh = (relopts && relopts->vacuum_max_threshold >= -1)
-		? relopts->vacuum_max_threshold
+	vac_max_thresh = (avopts && avopts->vacuum_max_threshold >= -1)
+		? avopts->vacuum_max_threshold
 		: autovacuum_vac_max_thresh;
 
-	vac_ins_scale_factor = (relopts && relopts->vacuum_ins_scale_factor >= 0)
-		? relopts->vacuum_ins_scale_factor
+	vac_ins_scale_factor = (avopts && avopts->vacuum_ins_scale_factor >= 0)
+		? avopts->vacuum_ins_scale_factor
 		: autovacuum_vac_ins_scale;
 
 	/* -1 is used to disable insert vacuums */
-	vac_ins_base_thresh = (relopts && relopts->vacuum_ins_threshold >= -1)
-		? relopts->vacuum_ins_threshold
+	vac_ins_base_thresh = (avopts && avopts->vacuum_ins_threshold >= -1)
+		? avopts->vacuum_ins_threshold
 		: autovacuum_vac_ins_thresh;
 
-	anl_scale_factor = (relopts && relopts->analyze_scale_factor >= 0)
-		? relopts->analyze_scale_factor
+	anl_scale_factor = (avopts && avopts->analyze_scale_factor >= 0)
+		? avopts->analyze_scale_factor
 		: autovacuum_anl_scale;
 
-	anl_base_thresh = (relopts && relopts->analyze_threshold >= 0)
-		? relopts->analyze_threshold
+	anl_base_thresh = (avopts && avopts->analyze_threshold >= 0)
+		? avopts->analyze_threshold
 		: autovacuum_anl_thresh;
 
-	freeze_max_age = (relopts && relopts->freeze_max_age >= 0)
-		? Min(relopts->freeze_max_age, autovacuum_freeze_max_age)
+	freeze_max_age = (avopts && avopts->freeze_max_age >= 0)
+		? Min(avopts->freeze_max_age, autovacuum_freeze_max_age)
 		: autovacuum_freeze_max_age;
 
-	multixact_freeze_max_age = (relopts && relopts->multixact_freeze_max_age >= 0)
-		? Min(relopts->multixact_freeze_max_age, effective_multixact_freeze_max_age)
+	multixact_freeze_max_age = (avopts && avopts->multixact_freeze_max_age >= 0)
+		? Min(avopts->multixact_freeze_max_age, effective_multixact_freeze_max_age)
 		: effective_multixact_freeze_max_age;
 
-	av_enabled = (relopts ? relopts->enabled : true);
+	av_enabled = (avopts ? avopts->enabled : true);
 
 	/* Force vacuum if table is at risk of wraparound */
 	xidForceLimit = recentXid - freeze_max_age;
-- 
2.39.5 (Apple Git-154)


--QWBYbd5Ar5k8NvSv
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0002-autovac-resolve-relopts-before-vacuuming.patch



^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v1] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl |  8 ++--
 src/backend/commands/prepare.c             | 43 +++++++++++++++++++--
 src/test/regress/expected/prepare.out      | 44 +++++++++++++---------
 src/test/regress/sql/prepare.sql           |  2 +-
 4 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 6af5ac1da18..535c4770095 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..11b330ab73d 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--biRhQYMBrGQlqcCN--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v2] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  2 +-
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 27 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index fe0478ac552..9a6bda90070 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -21,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel plancache cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing prepare
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 079a8eb5afc..65258651bd2 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -59,6 +59,7 @@ tests += {
       'cleanup',
       'oldextversions',
       'squashing',
+      'prepare',
     ],
     'regress_args': ['--temp-config', files('pg_stat_statements.conf')],
     # Disabled because these tests require
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--soawQPnav6xcFtRL--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread

* [PATCH v3] Cleanup explicit PREPARE query strings
@ 2025-12-24 14:31  Julien Rouhaud <[email protected]>
  0 siblings, 0 replies; 340+ messages in thread

From: Julien Rouhaud @ 2025-12-24 14:31 UTC (permalink / raw)

When a multi statements query string contains one PREPARE statement (or
multiple), the whole query string was saved in the cached plan.  This is
wasteful as that string can be artitrarily big, but it can also confusing as
some other parts like pg_prepared_statements will output the saved query string
as-is.

This commit changes this behavior and only stores the part of the query string
that correspond to any given PREPARED statement, similarly to how it's already
done in pg_stat_statements.
---
 contrib/auto_explain/t/001_auto_explain.pl    |  8 +--
 contrib/pg_stat_statements/Makefile           |  1 +
 .../pg_stat_statements/expected/prepare.out   | 53 +++++++++++++++++++
 contrib/pg_stat_statements/meson.build        |  1 +
 contrib/pg_stat_statements/sql/prepare.sql    | 15 ++++++
 src/backend/commands/prepare.c                | 45 ++++++++++++++--
 src/test/regress/expected/prepare.out         | 44 +++++++++------
 src/test/regress/sql/prepare.sql              |  2 +-
 8 files changed, 143 insertions(+), 26 deletions(-)
 create mode 100644 contrib/pg_stat_statements/expected/prepare.out
 create mode 100644 contrib/pg_stat_statements/sql/prepare.sql

diff --git a/contrib/auto_explain/t/001_auto_explain.pl b/contrib/auto_explain/t/001_auto_explain.pl
index 5f673bd14c1..f2d8625f8bb 100644
--- a/contrib/auto_explain/t/001_auto_explain.pl
+++ b/contrib/auto_explain/t/001_auto_explain.pl
@@ -60,7 +60,7 @@ $log_contents = query_log($node,
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1;/,
+	qr/Query Text: PREPARE get_proc\(name\) AS SELECT \* FROM pg_proc WHERE proname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -82,7 +82,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 like(
@@ -98,7 +98,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1;/,
+	qr/Query Text: PREPARE get_type\(name\) AS SELECT \* FROM pg_type WHERE typname = \$1/,
 	"prepared query text logged, text mode");
 
 unlike(
@@ -164,7 +164,7 @@ $log_contents = query_log(
 
 like(
 	$log_contents,
-	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1;"/,
+	qr/"Query Text": "PREPARE get_class\(name\) AS SELECT \* FROM pg_class WHERE relname = \$1"/,
 	"prepared query text logged, json mode");
 
 like(
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index c27e9529bb6..ac967687796 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -36,6 +36,7 @@ REGRESS = \
 	parallel \
 	plancache \
 	squashing \
+	prepare \
 	cleanup \
 	oldextversions
 
diff --git a/contrib/pg_stat_statements/expected/prepare.out b/contrib/pg_stat_statements/expected/prepare.out
new file mode 100644
index 00000000000..010e289c1b0
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/prepare.out
@@ -0,0 +1,53 @@
+-- Tests for PREPARE
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+ ?column? 
+----------
+        1
+(1 row)
+
+ ?column? | ?column? 
+----------+----------
+        1 |        1
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | SELECT $1
+     1 |    1 | SELECT $1, $2
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+EXECUTE p1;
+ ?column? 
+----------
+        1
+(1 row)
+
+EXECUTE p2(0);
+ ?column? 
+----------
+        0
+(1 row)
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls | rows |                       query                        
+-------+------+----------------------------------------------------
+     1 |    1 | PREPARE p1 AS SELECT 1
+     1 |    1 | PREPARE p2(int) AS SELECT 2 * $1
+     1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(3 rows)
+
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 9d78cb88b7d..c9e1d446d39 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -58,6 +58,7 @@ tests += {
       'parallel',
       'plancache',
       'squashing',
+      'prepare',
       'cleanup',
       'oldextversions',
     ],
diff --git a/contrib/pg_stat_statements/sql/prepare.sql b/contrib/pg_stat_statements/sql/prepare.sql
new file mode 100644
index 00000000000..a6bc5de4430
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/prepare.sql
@@ -0,0 +1,15 @@
+-- Tests for PREPARE
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Test that prepared statements in a multi-query string behaves as expected
+SELECT 1\;PREPARE p1 AS SELECT 1\; PREPARE p2(int) AS SELECT 2 * $1\; SELECT 1, 1;
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+EXECUTE p1;
+EXECUTE p2(0);
+
+SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 5b86a727587..b8fe3dd5302 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -27,6 +27,7 @@
 #include "commands/prepare.h"
 #include "funcapi.h"
 #include "nodes/nodeFuncs.h"
+#include "nodes/queryjumble.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"
@@ -64,6 +65,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	Oid		   *argtypes = NULL;
 	int			nargs;
 	List	   *query_list;
+	const char *new_query;
 
 	/*
 	 * Disallow empty-string statement name (conflicts with protocol-level
@@ -80,14 +82,49 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 */
 	rawstmt = makeNode(RawStmt);
 	rawstmt->stmt = stmt->query;
-	rawstmt->stmt_location = stmt_location;
-	rawstmt->stmt_len = stmt_len;
+
+	/*
+	 * Extract the query text if possible.
+	 *
+	 * If we have a statement location, we can extract the relevant part of the
+	 * possibly multi-statement query string.  If not just use what we were
+	 * given.
+	 */
+	if (stmt_location < 0)
+	{
+		rawstmt->stmt_location = stmt_location;
+		rawstmt->stmt_len = stmt_len;
+		new_query = pstate->p_sourcetext;
+	}
+	else
+	{
+		const char *cleaned;
+		char	   *tmp;
+
+		rawstmt->stmt_len = stmt_len;
+		cleaned = CleanQuerytext(pstate->p_sourcetext, &stmt_location,
+								 &rawstmt->stmt_len);
+
+		if (rawstmt->stmt_len == 0)
+			rawstmt->stmt_len = strlen(cleaned);
+
+		/*
+		 * CleanQuerytext() removes any leading whitespace and returns a
+		 * pointer to the first actual character, so the cleaned query string
+		 * is guaranteed to start at offset 0.
+		 */
+		rawstmt->stmt_location = 0;
+		tmp = palloc(rawstmt->stmt_len + 1);
+		strlcpy(tmp, cleaned, rawstmt->stmt_len + 1);
+
+		new_query = tmp;
+	}
 
 	/*
 	 * Create the CachedPlanSource before we do parse analysis, since it needs
 	 * to see the unmodified raw parse tree.
 	 */
-	plansource = CreateCachedPlan(rawstmt, pstate->p_sourcetext,
+	plansource = CreateCachedPlan(rawstmt, new_query,
 								  CreateCommandTag(stmt->query));
 
 	/* Transform list of TypeNames to array of type OIDs */
@@ -116,7 +153,7 @@ PrepareQuery(ParseState *pstate, PrepareStmt *stmt,
 	 * information about unknown parameters to be deduced from context.
 	 * Rewrite the query. The result could be 0, 1, or many queries.
 	 */
-	query_list = pg_analyze_and_rewrite_varparams(rawstmt, pstate->p_sourcetext,
+	query_list = pg_analyze_and_rewrite_varparams(rawstmt, new_query,
 												  &argtypes, &nargs, NULL);
 
 	/* Finish filling in the CachedPlanSource */
diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 5815e17b39c..c645a4e5d0e 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -6,7 +6,17 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+-----------+-----------------+--------------
 (0 rows)
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
+ ?column? 
+----------
+ bingo
+(1 row)
+
+ ?column? 
+----------
+       42
+(1 row)
+
 EXECUTE q1;
  a 
 ---
@@ -14,9 +24,9 @@ EXECUTE q1;
 (1 row)
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 1 AS a; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 1 AS a | {}              | {integer}
 (1 row)
 
 -- should fail
@@ -33,18 +43,18 @@ EXECUTE q1;
 
 PREPARE q2 AS SELECT 2 AS b;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q1   | PREPARE q1 AS SELECT 2;      | {}              | {integer}
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q1   | PREPARE q1 AS SELECT 2      | {}              | {integer}
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (2 rows)
 
 -- sql92 syntax
 DEALLOCATE PREPARE q1;
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
- name |          statement           | parameter_types | result_types 
-------+------------------------------+-----------------+--------------
- q2   | PREPARE q2 AS SELECT 2 AS b; | {}              | {integer}
+ name |          statement          | parameter_types | result_types 
+------+-----------------------------+-----------------+--------------
+ q2   | PREPARE q2 AS SELECT 2 AS b | {}              | {integer}
 (1 row)
 
 DEALLOCATE PREPARE q2;
@@ -168,20 +178,20 @@ SELECT name, statement, parameter_types, result_types FROM pg_prepared_statement
 ------+------------------------------------------------------------------+----------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------
  q2   | PREPARE q2(text) AS                                             +| {text}                                             | {name,boolean,boolean}
       |         SELECT datname, datistemplate, datallowconn             +|                                                    | 
-      |         FROM pg_database WHERE datname = $1;                     |                                                    | 
+      |         FROM pg_database WHERE datname = $1                      |                                                    | 
  q3   | PREPARE q3(text, int, float, boolean, smallint) AS              +| {text,integer,"double precision",boolean,smallint} | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR+|                                                    | 
       |         ten = $3::bigint OR true = $4 OR odd = $5::int)         +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q5   | PREPARE q5(int, text) AS                                        +| {integer,text}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
       |         SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2 +|                                                    | 
-      |         ORDER BY unique1;                                        |                                                    | 
+      |         ORDER BY unique1                                         |                                                    | 
  q6   | PREPARE q6 AS                                                   +| {integer,name}                                     | {integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,integer,name,name,name}
-      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;    |                                                    | 
+      |     SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2     |                                                    | 
  q7   | PREPARE q7(unknown) AS                                          +| {path}                                             | {text,path}
-      |     SELECT * FROM road WHERE thepath = $1;                       |                                                    | 
+      |     SELECT * FROM road WHERE thepath = $1                        |                                                    | 
  q8   | PREPARE q8 AS                                                   +| {integer,name}                                     | 
-      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1;           |                                                    | 
+      |     UPDATE tenk1 SET stringu1 = $2 WHERE unique1 = $1            |                                                    | 
 (6 rows)
 
 -- test DEALLOCATE ALL;
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index c6098dc95ce..0e7fe44725e 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -4,7 +4,7 @@
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
 
-PREPARE q1 AS SELECT 1 AS a;
+SELECT 'bingo'\;  PREPARE q1 AS SELECT 1 AS a \; SELECT 42;
 EXECUTE q1;
 
 SELECT name, statement, parameter_types, result_types FROM pg_prepared_statements;
-- 
2.52.0


--xBRJzsblsXcilRYX--





^ permalink  raw  reply  [nested|flat] 340+ messages in thread